METHOD OF MANUFACTURING BARREL OF AUTOMATIC SMALL ARMS Russian patent published in 2012 - IPC C21D9/12 B21D31/00 

FIELD: metallurgy.

SUBSTANCE: barrel workpieces are obtained from alloyed steel in the composition of which the alloying elements as a whole provide high position of critical point AC1, the upper limit of carbon content of which is limited by 0.3%, then thermo-hardening is carried out with high speed of cooling in pearlitic temperature interval and with suppression of carbides separation process by austenite grain junction lines. The external and internal surface of barrel workpiece is mechanically processed. The shot travel is formed, barrel chamber is manufactured. Galvanic chrome is deposited on the surface of the bore with the following heating via the use of DC source with current pulsing and voltage not exceeding 1% of nominal, then chrome-coated bore is heated.

EFFECT: increase of bore life time, firing life by two or more times.

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